A checklist of halacarid and hydrachnid mites (Acari, Halacaridae & Hydrachnidia) associated with sponges (Porifera) Author Chatterjee, Tapas text Zootaxa 2021 2021-11-29 5072 2 101 129 journal article 3184 10.11646/zootaxa.5072.2.1 37781dcd-ffff-4c1e-9483-fb726b42b440 1175-5326 5733656 F11C5EFE-8B45-4F58-B7E9-741D27EB47B6 Unionicola ( Hexatax ) nearctica Crowell & Davids, 1979 Report associated with sponges: This species was reported as sponge-associated mite in the Laurentian Great Lakes and St. Lawrence River basins, North America ( Crowell & Davids 1979 ). This species was mentioned by Crowell (1990) as developmentally associated with freshwater sponges in the Northern Hemisphere. This species was also mentioned under possible ‘sponge-mite’ species in North America ( Vidrine 1996 ; Edwards & Vidrine 2013 ). Remarks: This species belongs to ‘ U. crassipes —complex’. It needs further study (emphasizing on developmental study) of this mite to get better idea about association with freshwater sponges. Crowell & Davids (1979) stated “The distinctiveness of the North American U. crassipes- like mites makes it necessary to re-evaluate the records of those mites. The mites reported by Conroy (1974) were undoubtedly U. nearctica ”. [The paper presented by Conroy (1974) in IV International congress of Acarologie,Saalfelden, Austria , 1974 was published as Proceedings in 1979 and referred as Conroy, J.C. (1979)]. Crowell & Davids (1979) also commented: “The records of Wolcott (1899) and materials in the Ruth Marshall Collection appear to be a mixture of U. laurentiana and U. nearctica ”.